Retention Drainage Catheter

ABSTRACT

A multi-lumen catheter, for insertion into and draining a body cavity, that mitigates the risk of obstruction of the drainage ports and drainage lumen of the catheter, reduces the detrimental effects caused by the suction forces of the drainage ports on the body cavity being drained, and reduces the risk of infection of the body cavity being drained by decreasing the residual volume of fluid retained in the body cavity being drained. These advantages are achieved by the novel approach of disposing a perforated filter membrane or a membrane having a relatively large entry port(s) between membrane struts over a segmented retention element and also over the drainage port(s) of the drainage lumen of the catheter thereby creating internal interstitial drainage channels and internal interstitial drainage cavities.

CROSS-REFERENCES TO RELATED APPLICATIONS

This application is a continuation-in-part of U.S. application Ser. No.14/272,270, filed on May 7, 2014, which claims the benefit of U.S.Provisional Application Nos. 61/820,532, filed May 7, 2013, and61/826,869, filed May 23, 2013, each of which are incorporated herein byreference in their entirety.

FIELD OF THE INVENTION

The invention relates generally to medical devices and, in particular,to retention drainage catheters.

BACKGROUND OF THE INVENTION

In the medical field, catheters are generally used to drain fluids froma body cavity. In the urology field, a Foley retention drainagecatheter, which may be interchangeably referred to as a Foley catheteror drainage catheter, is commonly used to drain a human bladder. Thereare many medical conditions that necessitate the use of a Foleycatheter. The collection of urine and other fluids after a surgicalprocedure is such a condition. For the past seventy to eighty years theFoley retention drainage catheter, as depicted in FIG. 18 and labeled“PRIOR ART,” has been the preferred option to drain and collect urineand other fluids from the bladder. The basic design of a Foley cathetercomprises an elongated cylindrical element containing a central drainagelumen running the length of the elongated cylindrical element, havingone or more drainage ports in series at or near the distal end, and anexpandable retention element, located proximal to the drainage ports,for securing the catheter within the bladder. The retention element isexpanded with fluid via an inflation lumen running from the inflationvalve located on the proximal end of the elongated cylindrical elementto the retention element. The design of the Foley catheter has notundergone significant changes other than changes to the base materialsand attempts to give the materials antibacterial properties. Despite itscontinued use in the health care industry without significant designchanges the Foley catheter does have some acknowledged weaknesses.

Firstly, the Foley catheter is susceptible to obstruction of thedrainage ports and the drainage lumen of the catheter due to pluggingand/or buildup of debris (debris is defined as loose tissue, sediments,clotted blood, redundant bladder mucosa, and any other materials orviscous fluids in the clinical setting). The drainage ports aregenerally at least twice the cross sectional area of the drainage lumen.This can result in a funneling effect with debris draining into smallerand smaller spaces, thus, resulting in plugs and blockages causingcatheter obstruction. Further, due to the drainage ports being inseries, if the most proximal drainage port becomes obstructed by debristhat extend from the port into the drainage lumen, thus obstructing thedrainage lumen, any remaining unobstructed drainage ports are renderedineffective as they are upstream of the obstruction. Incompleteemptying/drainage of the bladder caused by obstructions in the catheterare significant causes of catheter associated urinary tract infections(UTIs).

Secondly, the drainage ports in the catheter, being limited in numberand limited in cumulative cross sectional area as related to the crosssectional area of the drainage lumen, create a suction effect so thatwhen the force of the suction is projected on the bladder mucosa thesuction can cause a disruption in the mucosal integrity. This can resultin increased risk of pain, bladder spasms, discomfort, and catheterassociated UTIs.

Thirdly, yet another problem is the inability of the Foley catheter tocompletely drain the bladder, even when the drainage system iscompletely free of obstruction. Due to the aforementioned drainage portlocations, when the bladder is actively drained during catheterization,and the bladder wall closes around the retention element, the bladderretains a residual volume of fluid that is not able to reach thedrainage ports. This volume of stagnant fluid can contain urine, blood,bacteria, and/or other pathogens that, when not regularly flushed out ofthe bladder, can set up an infection in the surrounding tissues, formblood clots in the bladder, and/or other conditions detrimental to thepatient. It should be understood that catheter associated UTIs are nowthe most expensive hospital acquired infection according to the Centersfor Disease Control and Prevention.

SUMMARY OF THE INVENTION

The aforementioned problems are solved and a technical advance isachieved in an illustrative novel multi-lumen filter membrane internalinterstitial drainage channel catheter (also referred to herein as aFMID catheter) for insertion into and draining a body cavity, thatmitigates the risk of obstruction of the drainage ports and drainagelumen of the catheter and also reduces the detrimental effects caused bythe suction forces of the drainage ports on the body cavity beingdrained, and reduces the risk of infection of the body cavity beingdrained by decreasing the residual volume of fluid retained in the bodycavity being drained. These advantages and more are achieved by thenovel approach of disposing a membrane (which may be perforated) over aretention element (which may be segmented), the proximal drainage ports,and the distal drainage ports of the drainage lumen of the catheter,such that when the retention element is expanded, the membrane createsone or more interstitial spaces or cavities between the membrane and theelongated cylindrical element (catheter tube).

When the retention element and membrane are in their expanded state,expandable cavities (henceforth referred to as internal interstitialdrainage cavities) are created between the membrane and the elongatedcylindrical element and expand as the membrane is pushed away fromelongated cylindrical element. Also, when a segmented retention elementand membrane are in their expanded state, other expandable cavities(henceforth referred to as internal interstitial drainage channels) arecreated between the expanded wedges of the retention element and themembrane in some embodiments. Alternatively, the interstitial drainagechannels can be disposed on a segmented retention element such that theyare not under the membrane when in the expanded state. The internalinterstitial drainage channels are disposed from the distal end of thesegmented retention element to the proximal end of the segmentedretention element and expand proportionally as the expanded state of thesegmented retention element and the membrane is reached. The drainageports communicate with the internal interstitial drainage cavities. Theinternal interstitial drainage cavities communicate with the internalinterstitial drainage channels. The internal interstitial drainagecavities and/or the internal interstitial drainage channels communicatewith the body cavity being drained through the membrane.

The membrane, in the expanded state, provides entry port(s) for fluid toenter into the interstitial drainage cavities and then through thedrainage ports of the FMID) catheter. One or more entry ports may belarger than the cross sectional area of the drainage ports and thedrainage lumen. While the relatively larger entry port size may allowfor debris (clots, tissue, etc.) larger than the drainage ports and thedrainage lumen to enter the interstitial drainage cavities and/orchannels, the relatively larger entry port size allows for decreasingthe suction force applied to the wall of the organ being drained. Thisdecreased force prevents unnecessary damage to the organ wall. In someembodiments, the membrane may also have portions, in the expanded state,that have a plurality of perforations wherein the individualperforations in the membrane have an equal or smaller cross sectionalarea than that of the drainage ports and the drainage lumen so thatdebris smaller than the perforations can pass through the membrane, thedrainage ports, and the drainage lumen without obstructing either.Debris larger than the perforations is stopped by the membrane whilestill leaving a plurality of perforations in the membrane unblocked,thus creating a drainage system in parallel rather than in series. Dueto there being a plurality of perforations in a portion of the membraneof these embodiments, the suction force produced by the drainage portsis distributed amongst all the perforations, thus mitigating thedetrimental effects of suction force on the tissues of the body cavitybeing drained. This FMID catheter is particularly advantageous whenpatients require an indwelling catheter and/or are at risk of having acatheter obstruction. Because the presently disclosed device improvesthe basic function of current Foley catheters without changing the wayit is implemented by the health care professional, it is expected toreplace the current Foley catheters as the standard of care.

BRIEF DESCRIPTION OF THE DRAWINGS

Further advantages of the invention will become apparent by reference tothe detailed description of preferred embodiments when considered inconjunction with the drawings which form a portion of the disclosure andwherein:

FIG. 1 depicts a pictorial view of an embodiment of a FMID catheter in acollapsed state.

FIG. 2 depicts a pictorial view of an embodiment of a FMID catheter inan expanded state.

FIG. 3 depicts an enlarged sectioned view of the distal portion of theFMID catheter shown in FIG. 2 taken along LINE 1-1.

FIG. 4 depicts an enlarged sectioned view of the distal portion of theFMID catheter shown in FIG. 2 taken along LINE 2-2.

FIG. 5 depicts an embodiment of a FMID catheter in an expanded statepositioned in a body cavity of a patient.

FIG. 6 depicts a pictorial view of an embodiment of a FMID catheter in acollapsed state with irrigation port and irrigation opening connector.

FIG. 7 depicts a pictorial view of an embodiment of a FMID catheter inan expanded state with irrigation port and irrigation opening connector.

FIG. 8 depicts a pictorial view of an embodiment of a FMID catheter in acollapsed state with perforated sleeve.

FIG. 9 depicts a pictorial view of an embodiment of a FMID catheter inan expanded state with perforated sleeve.

FIG. 10 depicts an enlarged sectioned view of the distal portion of theFMID catheter shown in FIG. 9 taken along LINE 4-4.

FIG. 11 depicts a pictorial view of an embodiment of a FMID catheter ina collapsed state with wire guide.

FIG. 12 depicts a pictorial view of an embodiment of a FMID catheter ina collapsed state with encapsulated distal end.

FIG. 13 depicts a pictorial view of an embodiment of a FMID catheter inan expanded state with encapsulated distal end.

FIG. 14 depicts an enlarged sectioned view of the distal portion of theFMID catheter shown in FIG. 13 taken along LINE 3-3.

FIG. 15 depicts an enlarged sectioned view of an embodiment of a FMIDcatheter in an expanded state.

FIG. 16 depicts an enlarged sectioned view of an embodiment of a FMIDcatheter in an expanded state.

FIGS. 17A, B, and C depict enlarged sectioned views of the elongatedcylindrical element of embodiments of a FMID catheter.

FIG. 18 depicts an exemplary PRIOR ART Foley retention drainagecatheter.

FIG. 19 depicts an enlarged sectioned view of the distal portion of anembodiment of a FMID catheter in an expanded state having relativelylarger membrane entry ports between membrane struts at both the proximaland distal ends of the retention element.

FIG. 20 depicts an enlarged sectioned view of the distal portion of anembodiment of a FMID catheter in an expanded state having relativelylarger membrane entry ports between membrane struts at only the proximalend of the retention element.

FIG. 21 depicts an enlarged sectioned view of the distal portion of anembodiment of a FMID catheter in an expanded state having relativelylarger membrane entry ports between membrane struts at only the distalend of the retention element.

DETAILED DESCRIPTION

The following detailed description is presented to enable any personskilled in the art to make and use the invention. For purposes ofexplanation, specific details are set forth to provide a thoroughunderstanding of the present invention. However, it will be apparent toone skilled in the art that these specific details are not required topractice the invention. Descriptions of specific applications areprovided only as representative examples. Various modifications to thepreferred embodiments will be readily apparent to one skilled in theart, and the general principles defined herein may be applied to otherembodiments and applications without departing from the scope of theinvention. The present invention is not intended to be limited to theembodiments shown, but is to be accorded the widest possible scopeconsistent with the principles and features disclosed herein.

For the purposes of this disclosure a Foley retention drainage catheter,which may be interchangeably referred to as a Foley catheter or drainagecatheter, and is commonly used to drain a human bladder, is discussed.However it should be understood that the same inventive featuresdescribed in this disclosure can be applied to other types of cathetersused in other parts of the bodies of both animals and humans in needthereof. Referring to the drawings for a better understanding of thefunction and structure of the invention, FIGS. 1 and 2 present anexemplary embodiment of the multi-lumen filter membrane internalinterstitial drainage channel catheter 20, referred to also as a FMIDcatheter 20. As shown in FIG. 1, the FMID catheter 20 is an improvementover the existing Foley catheter design. Like the existing Foleycatheter, the FMID catheter 20, is designed to be inserted into a bodycavity 21 of a patient in need thereof, which may include a human beingor another animal. Once inserted, the FMID catheter 20 can be used todrain fluids from, remove small debris from, and/or infuse fluids intoof the body cavity 21. In an exemplary embodiment, the FMID catheter 20is an indwelling catheter that is inserted through the urethral canal58, and in some cases the suprapubic tract, and then into the bladder59. It should be understood that the dimensions of the FMID catheter 20and its components can vary both as to length and diameter as needed orappropriate for a given procedure on a patient in need of draining abody cavity 21.

FIG. 3 depicts an enlarged sectioned view of the distal portion 72 ofthe embodiment of a FMID catheter 20 shown in FIG. 2 along LINE 1-1.FIG. 4 depicts an enlarged sectioned view of the distal portion 72 ofthe embodiment of a FMID) catheter 20 shown in FIG. 2 along LINE 2-2.FIG. 5 depicts an exemplary embodiment of a FMID catheter 20 positionedin a body cavity 21 (the bladder 59, as shown) of a patient. Once theFMID catheter 20 is in position, the segmented retention element 39surrounding a portion of the distal end 28 of the FMID catheter 20 isexpandable for inflation to the expanded state 40 and retains the FMIDcatheter 20 against the neck 78 of the bladder 59 until the segmentedretention element 39 is deflated for removal (the distal end 28 beingthe end of the catheter inserted into the body cavity 21 and theproximal end 29 being the end that remains outside of the body).Although segmented retention elements are preferred in many embodiments,it should be understood that some embodiments may include non-segmentedexpandable retention element 39. Unless specifically stated otherwise,it should be understood that the discussed embodiments could includeeither a segmented or non-segmented retention element 39. When included,the segmented retention element 39 can have an unlimited number ofsegments and/or as few as one segment. Preferred embodiments containfour symmetrical segments. The distal end 28 of a flexible elongatedcylindrical element 31 can be of hemispherical shape and/or other shapesas required per conditions specific to its intended use by a medicalprofessional. Pluralities of lumina (drainage lumen 23, inflation lumen46, and irrigation lumen 48) provide for functions comprising, but notlimited to, separate drainage, inflation, and irrigation, respectively.Preferred embodiments of the FMID catheter 20 will have at least twolumina (drainage lumen 23 and inflation lumen 46). In addition to theaforementioned characteristics, the FMID catheter 20 provides for aperforated filter membrane 24 encapsulating the retention element 39. Insome embodiments, however, the filter membrane 24 may be configured tonot encapsulate any of the segmented retention element 39. Theperforated filter membrane 24 is also disposed over the proximaldrainage ports 22 b and over the distal drainage ports 22 a of thedrainage lumen 23 of the FMID catheter 20. When in an expanded state 40the filter membrane 24 mitigates the chance of the drainage ports 22,drainage lumen 23, and drainage connector 51 of the FMID) catheter 20being obstructed by debris 73.

To retain the FMID catheter 20 in a body cavity 21 of a patient in needthereof, a segmented retention element 39 comprising one or moresubstantially spherical wedges 41 is disposed near the distal end 28 butproximal to the distal drainage ports 22 a and distal to the proximaldrainage ports 22 b. For example, see FIG. 3. One or more inflationports 44 are disposed on the flexible elongated cylindrical element 31underneath the segmented retention element 39. An inflation lumen 46 isdisposed within the elongated cylindrical element 31 from the inflationports 44 to the proximal end 29 of the elongated cylindrical element 31.In preferred embodiments, the inflation lumen 46 is positioned adjacentto the drainage lumen 23 and extending longitudinally within theelongated cylindrical element 31. One or more inflation valves 45 aredisposed at or near the proximal end 29. The valve(s) 45 can be ofvarious forms known in the art. The segmented retention element 39 is influid communication with the inflation ports 44. The inflation ports 44communicate with the inflation lumen 46. The inflation lumen 46communicates with the inflation valve 45. A removable syringe (notshown) communicating with the inflation valve 45 can be used to exert apositive pressure force on the segmented retention element 39, therebycausing inflation to an expanded state 40 of the segmented retentionelement 39. Similarly, a removable syringe (not shown) communicatingwith the inflation valve 45 can be used to exert a negative pressureforce on the segmented retention element 39, thereby causing deflationto a collapsed state 42 of the segmented retention element 39. Inflationof the segmented retention element 39 can be carried out by injectingair, gel, fluid, or other substance known in the art. Preferably, abiocompatible fluid, such as saline, water, and/or contrast media, isused to inflate the segmented retention element 39. Alternatively, thesegmented retention element 39 and/or the filter membrane 24 of the FMIDcatheter 20 can be mechanically expandable.

To drain the body cavity 21 of the patient, the FMID catheter 20includes a drainage lumen 23 extends longitudinally within the flexibleelongated cylindrical element 31 and having a drainage connector 51 atthe proximal end 29 of the elongated cylindrical element. Preferably,the drainage lumen 23 is disposed centrally within the elongatedcylindrical element 31. The drainage ports 22 can be of any size and/orshape and disposed anywhere along the elongated cylindrical element 31.Preferably, the drainage lumen 23 may have one or a plurality ofdrainage ports 22 disposed at least near the distal end 74 of theretention element 39 in fluid communication with the exterior, (e.g.,the body cavity 21 to be drained) of the FMID catheter 20. Inembodiments having a double-cone configuration, these preferably alsohave one or a plurality of drainage ports 22 disposed at least near theproximal end 68 of the retention element 39 in fluid communication withthe exterior, (e.g., the body cavity 21 to be drained) of the FMIDcatheter 20.

To mitigate the risk of obstruction to the drainage lumen 23 and thedrainage ports 22, a filter membrane 24 is included with its proximalend 36 affixed on the outer surface 67 of the flexible elongatedcylindrical element 31 near the proximal end 68 of the retention element39 and disposed proximal to the proximal drainage ports 22 b (referredto as the proximal membrane affixing point 70). The distal end 69 of thefilter membrane 24 is affixed on the outer surface 67 of the elongatedcylindrical element 31 near the distal end 28 and disposed distal to thedistal drainage ports 22 a (referred to as the distal membrane affixingpoint 71). The retention element 39 is preferably made of a soft andresilient material capable of expansion and deflation, such as silicone,latex rubber, synthetic latex, silicone-based composite materials,latex-based composite materials, and/or combinations of these. Suchmaterials will stretch or expand to the expanded state of the device andthen retract to the collapsed state of the device. It should beunderstood that the retention element 39 may be made of any acceptablematerial known in the art or later discovered to be acceptable forconstructing similar balloon catheters.

When the retention element 39 and the filter membrane 24 are in acollapsed state 42, the retention element 39 and the filter membrane 24lay substantially flat against the flexible elongated cylindricalelement 31 encapsulating but not affixed to the remaining portion of theretention element 39 or the elongated cylindrical element 31 between theproximal membrane affixing point 70 and distal membrane affixing points71. Some embodiments of the FMID) catheter 20 may include a portion ofthe elongated cylindrical element 31, for example, but not intended tobe limiting in any way, from one end of the retention element 39 to thedistal membrane affixing points 71 (i.e., substantially all of theportion inserted into the body cavity 21), that is made of a from andresilient material, such as biocompatible plastics or other materialsknown in the art. The firm and resilient material can be disposedcontinuously or in a series of rings within the aforementioned portion.It is understood that any other material and configuration of materialthat increases the stiffness of the catheter 20 at the aforementionedportion is contemplated. Thus, the FMID catheter 20 is to be insertedinto a body cavity 21 when in the collapsed state 42.

When the retention element 39 is in the expanded state 40, the filtermembrane 24 is expanded into a substantially double conical shape beinglargest in diameter near the retention element 39, and smallest indiameter at proximal membrane affixing point 70 and distal membraneaffixing points 71. This configuration causes the filer membrane 24 tobe held apart from the flexible elongated cylindrical element 31 to forminternal interstitial drainage cavities 27, one disposed near theproximal end 68 of the retention element 39 (27 a) and one disposed nearthe distal end 28 of the elongated cylindrical element 31 (27 b),between the filter membrane 24 and the elongated cylindrical element 31.The proximal 27 a and distal 27 b internal interstitial drainagecavities 27 are in fluid communication with the proximal 22 b and distaldrainage ports 22 a, respectively, to allow for fluids and/or debris toflow into the drainage ports 22. The internal interstitial drainagecavities 27 can be formed by masses, elements, and/or processesdifferent from those relating to the retention element 39 and/or thefilter membrane 24.

The filter membrane 24 has a plurality of perforations 47 that areindividually smaller in cross sectional area than the most constrictedportion of the drainage lumen 23 and the drainage ports 22 wherebypreventing debris 73 larger than the most constricted portion of thedrainage lumen 23 and the drainage ports 22 from entering an internalinterstitial drainage cavities 27. When the retention element 39 and thefilter membrane 24 are in the expanded state 40 a plurality of sizes andshapes of perforations 47 may result. Debris 73 smaller in crosssectional area than the cross sectional area of an individualperforation 47, and thus smaller than the most constricted portion ofthe drainage lumen 23 and the drainage ports 22, can pass freely throughthe filter membrane 24, drainage ports 22, and then through the drainagelumen 23 without causing obstruction. As the plurality of perforations47 in the filter membrane 24 provide a significantly greater total crosssectional drainage area than the total cross sectional drainage area ofthe drainage ports 22 and the drainage lumen 23 so that when debris 73larger than the perforations lodges in and/or over more than oneperforation 47, the rate of drainage is not substantially diminished orobstructed clue to the availability of a plurality of perforations 47.In the event that debris 73 does cover the filter membrane 24, aremovable syringe (not shown) can be connected to the drainage connector51. A negative pressure force can be applied, by use of the removablesyringe, to the perforations 47 to aspirate debris 73 through theperforations 47, through the internal interstitial drainage cavities 27,through the internal interstitial drainage channels 26, through thedrainage ports 22, and through the drainage lumen 23, A positivepressure force can be applied, by use of the removable syringe, to theperforations 47 to flush debris 73 out of and/or away from theperforations 47.

The filter membrane 24 may include perforations 47 that are round inshape and/or any other shape and may be of varying size. In addition toor in the alternative to a plurality of perforations 47, someembodiments of the FMID catheter 20 may include a filter membrane 24comprising a material with passive diffusion characteristics that wouldallow the free flow of fluids and dissolved materials through themembrane while blocking debris 73. Other embodiments may include afilter membrane 24 having a configuration and/or construction that doesnot possess the qualities and/or characteristics of a membrane, such as,but not intended to be limiting, open cell foam and/or sponge materialscould be utilized. The distal end 69 of the filter membrane 24 can benon-perforated. The filter membrane 24 may additionally have ribs (notshown) extending from the proximal membrane affixing point 70 to thedistal membrane affixing point 71 to provide structural support for thefilter membrane 24 while in the expanded state 40.

Due to there being a plurality of perforations 47 in the filter membrane24, the suction force produced by the drainage ports 22 is dispersedamongst all the perforations 47, thus resulting in a greatly reducedrate of fluid flowing through any individual perforation 47 as comparedto the rate of fluid flowing through any individual drainage port 22.Thus, a significant suction force is not created by individualperforations 47. This characteristic causes debris 73 to not be readilydrawn to the filter membrane 24, as it would be drawn to an unfiltereddrainage port, which reduces the chance of debris buildup on the filtermembrane 24. This characteristic also reduces the detrimental effects offocal suction force projected on the tissues of the body cavity 21 beingdrained, particularly the bladder mucosa 32, the irritation of which cancause an increased risk of catheter associated UTIs and/or other damageto the mucosa. Catheter associated UTIs are now the most expensivehospital acquired infection according to the Centers for Disease Controland Prevention (CDC).

To provide for enhanced drainage when the segmented retention element 39and filter membrane 24 are in their expanded state 40, expandableinternal interstitial drainage cavities 27 are created between thefilter membrane 24 and the flexible elongated cylindrical element 31,which expand as the filter membrane is pushed away from the elongatedcylindrical element 31. Also, when the segmented retention element 39and filter membrane 24 are in their expanded state 40, expandableinternal interstitial drainage channels 26 are created between thespherical wedges 41 of the retention element 39 and the filter membrane24. The internal interstitial drainage channels 26 are disposed from thedistal end 74 of the segmented retention element 39 to the proximal end68 of the segmented retention element 39 and expand proportionally asthe expanded state of the segmented retention element 39 and the filtermembrane 24 is reached. The internal interstitial drainage channels 26can be formed by masses, elements, and/or processes different from thoserelating to the retention element 39 and/or the filter membrane 24. Asstated above, the drainage ports 22 are in fluid communication with theinternal interstitial drainage cavities 27. The internal interstitialdrainage cavities 27 are in fluid communication with the internalinterstitial drainage channels 26. The internal interstitial drainagecavities 27 and/or the internal interstitial drainage channels 26 are influid communication with the body cavity 21 being drained through thefilter membrane 24. The internal interstitial drainage channels 26advantageously allow for more surface area of the distal portion 72 ofthe FMID catheter 20 to drain the body cavity 21, as well as fluidcommunication between the internal interstitial drainage cavities 27.This configuration also advantageously allows for continued drainagethrough one drainage port 22 in the event that the other becomesobstructed.

Some embodiments of the FMID catheter 20 may have an irrigation lumen 48disposed in the flexible elongated cylindrical element 31 and extendinglongitudinally within the elongated cylindrical element 31, having anirrigation opening connector 50 at the proximal end 29 of the elongatedcylindrical element 31. The irrigation lumen 48 may have one or moreirrigation ports 49 disposed along the elongated cylindrical element 31.The irrigation port(s) 49 can be of any size and/or shape and disposedanywhere along the elongated cylindrical element 31. Preferably, theirrigation port(s) 49 at and/or near the distal end 28, in fluidcommunication with the exterior 66 of the FMID catheter 20, and locateddistal to the filter membrane 24 for delivering an irrigating solutionto the body cavity 21 being drained. FIGS. 6 and 7 depict a pictorialview of illustrative embodiment of a FMID catheter 20 having anirrigation lumen 48. A normal saline and/or sterile water irrigatingfluid may be delivered to the body cavity 21 in order to preventpostoperative and/or spontaneous blood clot retention. The irrigatingfluid may also be delivered to the body cavity 21 being drained tocleanse and/or administer medicines for treating conditions, such asbacteriuria.

Other embodiments of FMID catheter 20 may have a plurality of separatesub-retention elements 75 in the segmented retention element 39 that areformed by disposing a perforated sleeve 52 around the collapsedretention element 39. When being put into an expanded state, theretention element 39 expands through the perforations in the perforatedsleeve 52 creating one and or more sub-retention elements 75. FIGS. 8and 9 depict a pictorial view of a FMID catheter 20 having a perforatedsleeve 52 and sub-retention elements 75. FIG. 10 depicts an enlargedsectioned view of the distal portion 72 of the embodiment of a FMIDcatheter 20 shown in FIG. 9 along LINE 4-4. The separate sub-retentionelements 75 in the segmented retention element 39 due to the perforatedsleeve 52 may create larger interstitial drainage channels 26.

Some embodiments of the FMID catheter 20 may have at least one drainageport 22 c disposed at the distal end 28 of the flexible elongatedcylindrical element 31. This configuration permits the catheter 20 to beinserted over a guidewire 57 through the drainage lumen 23 and theaforementioned drainage port 22 c disposed on the distal end 28. Thisconfiguration is especially useful in various surgical procedures, suchas those needing cystoscopic access to the bladder 32 or body cavity 21with subsequent need for leaving a catheter in situ. A guidewire 57 isplaced under direct vision using a cystoscope. The cystoscope is removedleaving the guidewire 57 in place within the bladder 32 or body cavity21, on which the catheter, such as FMID catheter 20, may be guided.

In addition, endoscopic instruments and other medical devices, forexample, but not limited to cystoscopes, ureteroscopes, temperatureprobes, microwave thermotherapy probes, radiofrequency ablation probes,urodynamic catheters, etc. can likewise be inserted through the FMIDcatheter 20 using drainage lumen 23 (with or without the aid ofguidewire 57) for access to the bladder 32 or body cavity 21. FIG. 11depicts a pictorial view of a FMID catheter 20 as described in thisembodiment.

Further embodiments of the FMID catheter 20 may include a distalmembrane affixing point 71 of the filter membrane 24 disposed at thedistal end 28 of the flexible elongated cylindrical element 31 such thatthe distal membrane affixing point 71 seats into and encapsulates thedistal end 28. The distal membrane affixing point 71 of the filtermembrane 24 may and/or may not be perforated. FIGS. 12 and 13 depict apictorial view of a FMID catheter 20 as described in this embodiment.Furthermore, some embodiments may include a filter membrane 24configured to encapsulate only a portion of the segmented retentionelement 39. FIG. 14 depicts an enlarged sectioned view of the distalportion of a FMID catheter with a partially encapsulating filtermembrane. Thus, in some embodiments, the proximal membrane affixingpoint 70 may be on the proximal end 68 of the retention element 39. Notethat no proximal drainage port 22 b is necessary in this embodiment.Nevertheless, a segmented retention element 39 may be used to createinternal interstitial drainage channels 26 and more surface area fordrainage through the plurality of perforations 47.

Still further embodiments of the FMID catheter 20 may include aperforated retention element 64 of which the perforations 47 areconfigured as drainage lumina 62. The perforated retention element 64can be comprised of multiple layers. Disposed between the multiplelayers of the perforated retention element 64 are inflation cavities 77which are in fluid communication with the inflation port 44 andinflation lumen 46. The flexible elongated cylindrical element 31(internal to the perforated retention element 64) may have one or moredrainage ports 65 in fluid communication with the drainage lumen 23.Internal 53 to the perforated retention element 64 are drainage cavities61 which are in fluid communication with the body cavity 21 beingdrained and the drainage port 65 and drainage lumen 23. It is alsoenvisioned that the perforated retention element 64 can be comprised ofa single layer that would be mechanically and/or by means other thaninflation cavities deployed to an expanded state 40. The perforatedretention element 64 would perform the job of both the segmentedretention element 39 and the filter membrane 24 thus reducing the sizeof the unit so less patient discomfort is experienced. It could alsoreduce the cost and increase production efficiency. FIG. 15 depicts anenlarged sectioned view of a FMID catheter 20 having a perforatedretention element 64.

Still further embodiments of the FMID catheter 20 may include theretention element 39 comprised of one and or a plurality of individuallyinflated sub-retention elements 75. The sub-retention elements 75 can bedisposed on the flexible elongated cylindrical element 31 radially,non-radially, and/or otherwise. In some embodiments, the sub-retentionelements 75 can be inflated individually by separate inflation lumen 46.FIG. 16 depicts an enlarged sectioned view of the distal portion of aFMID catheter 20 having retention element 39 comprised four individuallyinflated sub-retention elements 75.

It is to be understood that various embodiments of the FMID catheter 20described above may also include one and or more of the followingcharacteristics: The flexible elongated cylindrical element 31 of theFMID catheter 20 may take a shape other than cylindrical as required perconditions such as, but not limited to, trabeculated bladders, bladderdiverticula, neobladders, and bladders with large prostate median lobesprotruding into the bladder. FIGS. 17A-C depicts multiple sectionalviews of an elongated cylindrical element 31 having various internalstructural shapes.

Now turning to FIGS. 19-21, which are depicting a pictorial view ofstill further embodiments of a FMID catheter 20 having one or morerelatively larger membrane entry ports 81 disposed between membranestruts 83 in an expanded state. As can be appreciated in FIGS. 19-21,some embodiments may include a filter membrane 24 configured toencapsulate only a portion of the retention element 39 and/or onlypartially cover the retention element 39. FIG. 19 depicts an enlargedsectioned view of the distal portion of a FMID catheter 20 with apartially covering filter membrane 24. Here, the partially coveringfilter membrane 24 expands to reveal relatively larger membrane entryports 81 between membrane struts 83 at the distal 74 and proximal ends68 of the retention element 39. The membrane entry ports 81 open to theinterstitial drainage cavities 27 (that exist once the retention element39 is expanded and enlarge as the filter membrane 24 is pushed away fromelongated cylindrical element 31) defined by the void at the distal 74and proximal ends 68 of the retention element 39 between the elongatedcylindrical element 31 and the filter membrane 24. The filter membrane24 may include perforations to allow for further membrane entry ports 82into the interstitial drainage cavities 27. The membrane entry ports 81and/or 82 could be of any shape and any size with a cross-sectional areathat is equal or larger than the drainage port(s) 22.

In some embodiments, as shown in FIG. 20, the filter membrane 24encapsulates only the distal end 74 cavity 27 of the retention element39 with a plurality of perforations 47 as previously described, andhaving relatively larger membrane entry ports 81 between membrane struts83 at the proximal end 68 cavity 27. In still other embodiments, asshown in FIG. 21, the filter membrane has relatively larger membraneentry ports 81 between membrane struts 83 at the distal end 74 cavity 27without an encapsulating membrane 24 portion, or with a proximal end 68encapsulating membrane 24 portion (not shown).

Thus, the relatively larger membrane entry ports 81 between membranestruts 83 reduce the detrimental effects caused by the suction forces ofthe drainage ports 22 on the body cavity being drained, and reduce therisk of infection of the body cavity being drained by decreasing theresidual volume of fluid retained in the body cavity being drained.Other features described above for the retention drainage catheters mayalso be incorporated into the embodiments having the relatively largermembrane entry ports 81 between membrane struts 83. As described above,internal interstitial drainage channels 26 may be created between theexpanded wedges of a segmented retention element 39 and the filtermembrane 24 in some embodiments so that the cavities 27 are incommunication. Alternatively, the interstitial drainage channels 26 canbe disposed on a segmented retention element 39 such that they (26) arenot under the filter membrane 24 when in the expanded state. Also notethat the proximal drainage port 22 b is optional in this embodiment.

The invention further provides methods of manufacturing the FMID)catheter 20 such as would be apparent to one of skill in the art giventhe disclosure and objectives of this disclosure. The FMID catheter 20can be configured into any number of catheter designs comprising but notlimited to, straight Foley, Coude’ tip Foley, Council tip Foley, 3-wayFoley, Whistle tip, spanning tandem balloon, Malecot catheters, subsumedtip, and any other catheter design presently existing or developed inthe future. The FMID catheter 20 being of a material comprising at leastone from a group of any biologically inert, biologically non-inert,naturally occurring, synthetic, non-biodegradable, biodegradable, andbioresorbable materials now known or later discovered in the future thatare acceptable within the art for manufacturing catheter components,comprising but not limited to elastomeric materials, polymers,copolymers, metals and metal alloys. Exemplary materials areelastomeric, latex, and silicone. The retention element 39 and filtermembrane 24 components are preferably made of an expandable silicone,latex rubber, silicone-based material, latex-based material, and/orcombinations thereof. In some embodiments, especially where the filtermembrane 24 possesses membrane properties, elastomeric material havingmicro-pores for filtering fluids and/or dissolved materials may beutilized. Thermo-sensitive materials, which change resiliency and orsize at different temperatures, are contemplated to be within the scopeof the disclosure. The filter membrane 24 and/or the retention element39/64 may be affixed by any known method, including by adhesive,heat/chemical welding, mechanical fasteners, and/or combinationsthereof. Preferably, a biocompatible latex or silicone adhesive is used.

The FMID catheter 20 can be coated or impregnated with therapeuticagents, such as but not limited to, antibiotics, antiseptics, bloodclotting factors, growth factors, steroids, or any other materials andsubstances now known or later discovered in the future. The FMIDcatheter 20 can be coated or impregnated with fluorescent or radiopaquematerials for radiological imaging. Applicants intend to encompass anystructure presently existing or developed in the future that performsthe same function.

The terms “comprising,” “including,” and “having,” as used in the claimsand specification herein, shall be considered as indicating an opengroup that may include other elements not specified. The terms “a,”“an,” and the singular forms of words shall be taken to include theplural form of the same words, such that the terms mean that one or moreof something is provided. The term “one” or “single” may be used toindicate that one and only one of something is intended. Similarly,other specific integer values, such as “two,” may be used when aspecific number of things is intended. The terms “preferably,”“preferred,” “prefer,” “optionally,” “may,” and similar terms are usedto indicate that an item, condition or step being referred to is anoptional (not required) feature of the invention.

The FMID catheter 20 and methods have been described with reference tovarious specific and preferred embodiments and techniques. However, itshould be understood that many variations and modifications may be madewhile remaining within the spirit and scope of the invention. It will beapparent to one of ordinary skill in the art that methods, devices,device elements, materials, procedures and techniques other than thosespecifically described herein can be applied to the practice of theinvention as broadly disclosed herein without resort to undueexperimentation. All art-known functional equivalents of methods,devices, device elements, materials, procedures and techniques describedherein are intended to be encompassed by this invention.

While the invention has been described with respect to a limited numberof embodiments, those skilled in the art, having benefit of thisdisclosure, will appreciate that other embodiments can be devised whichdo not depart from the scope of the invention as disclosed herein. Thisinvention is not to be limited by the embodiments disclosed, includingany shown in the drawings or exemplified in the specification, which aregiven by way of example and not of limitation. Accordingly, the scope ofthe invention should be limited only by the attached claims.

We claim:
 1. A device affixed to a drainage catheter for preventing debris from entering said drainage catheter comprising a filter membrane having at least one membrane entry port disposed between membrane struts.
 2. The device of claim 1, wherein the filter membrane is disposed over a distal portion of a flexible elongated cylindrical element having a proximal end and a distal end for inserting into a body cavity and an expandable retention element having a proximal end and a distal end.
 3. The device of claim 2, wherein the flexible elongated cylindrical element has at least one drainage port with a cross sectional drainage area in fluid communication with a drainage lumen disposed within the flexible elongated cylindrical element.
 4. The device of claim 3, wherein said at least one membrane entry port disposed between membrane struts has an individual cross sectional area that is equal to or larger than the cross sectional drainage area of the at least one drainage port.
 5. The device of claim 4, wherein the filter membrane is affixed to the flexible elongated cylindrical element near said distal end of the flexible elongated cylindrical element and near said proximal end of the expandable retention element such that the at least one drainage port is covered by the filter membrane.
 6. The device of claim 4, wherein the at least one drainage port is at least two drainage ports, and wherein the filter membrane is affixed to the flexible elongated cylindrical element near said distal end of the flexible elongated cylindrical element and near said proximal end of the expandable retention element such that the at least two drainage ports are covered by the filter membrane.
 7. The device of claim 6, wherein the at least one membrane entry port disposed between membrane struts is at least two membrane entry ports disposed between membrane struts and wherein at least one each of the at least two membrane entry ports disposed between membrane struts is disposed at the proximal end and the distal end of the expandable retention element.
 8. The device of claim 6, wherein the at least one membrane entry port disposed between membrane struts is disposed at the proximal end of the expandable retention element and wherein the filter membrane at the distal end of the expandable retention element includes a plurality of perforations.
 9. The device of claim 4, wherein the at least one membrane entry port disposed between membrane struts is disposed at the distal end of the expandable retention element.
 10. A device comprising: a flexible elongated cylindrical element having a distal portion with a distal end for inserting into a body cavity, a proximal end, and also having at least two lumina disposed within the flexible elongated cylindrical element; a filter membrane having at least one membrane entry port and affixed to the flexible elongated cylindrical element at the distal portion; and an expandable retention element in fluid communication with at least a first lumen of said at least two lumina within the flexible elongated cylindrical element, wherein the expandable retention element is disposed between the flexible elongated cylindrical element and the filter membrane.
 11. The device of claim 10, wherein the expandable retention element has a first non-expanded state in which the expandable retention element and the filter membrane lay substantially flat against the flexible elongated cylindrical element.
 12. The device of claim 11, wherein the expandable retention element has a second expanded state in which the expandable retention element is filled with a fluid and the filter membrane expands with the filled expandable retention element.
 13. The device of claim 12, further comprising at least one drainage port disposed on the flexible elongated cylindrical element in fluid communication with at least a second lumen of said at least two lumina within the flexible elongated cylindrical element for draining said body cavity.
 14. The device of claim 13, wherein the filter membrane is affixed to the flexible elongated cylindrical element near said distal end and near the proximal end of the expandable retention element such that the at least one drainage port is covered by the filter membrane.
 15. The device of claim 13, wherein the filter membrane is affixed to the flexible elongated cylindrical element near said distal end and near the proximal end of the expandable retention element such that the at least two drainage ports are covered by the filter membrane.
 16. The device of claim 13, further comprising a distal internal interstitial drainage cavity and a proximal internal interstitial drainage cavity between the filter membrane and the flexible elongated cylindrical element.
 17. The device of claim 16, wherein the retention element is comprised of a plurality of separate sub-retention element members.
 18. The device of claim 15, wherein the at least one membrane entry port is at least two membrane entry ports and wherein at least one each of the at least two membrane entry ports is disposed at the proximal end and the distal end of the expandable retention element.
 19. The device of claim 15, wherein the at least one membrane entry port is disposed at the proximal end of the expandable retention element and wherein the filter membrane at the distal end of the expandable retention element includes a plurality of perforations. 